Optical Systems Design OSD8826 Series, Operator'S Manual

Page: 12 / 20

OPTICAL SYSTEMS DESIGN
DOC ID: 10110306
OSD8826 OPERATOR MANUAL
PAGE 12
2.4 DATA MODE SWITCH SETTINGS
The 3-way data control switch is located at the front of OSD8826 modem. Switches SW1, SW2 and
SW3 are used for setting the Data Mode Options.
Note:
For correct operation, ensure that both OSD8826T and OSD8826R have the switch settings in
the same modes.
TABLE 4: DATA MODE SWITCH SETTINGS
SWITCH STATE POSITION FUNCTION
SW1
OFF DOWN RS422/485
ON UP RS232
SW2
OFF DOWN 4-Wire Operation
ON UP 2-Wire Operation
SW3
OFF DOWN RS422
ON UP RS485
FIGURE 5: DATA SWITCH DIAGRAMS
TABLE 5: DATA SWITCH EXAMPLES
DATA TYPE SW1 SW2 SW3
RS232
1 X X
RS422
0 X 0
RS485 2W
0 1 1
RS485 4W
0 0 1
1=On, 0=Off, X=Don’t Care
Switch setting is example
only
ON
OFF
1 2 3
Mode Switch